GB2174182A

GB2174182A - Improvements in or relating to underwater lamps

Info

Publication number: GB2174182A
Application number: GB08510588A
Authority: GB
Inventors: David Ronald Barnes
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-04-25
Filing date: 1985-04-25
Publication date: 1986-10-29
Also published as: GB8510588D0

Abstract

An underwater lamp for use by divers and others has a hollow body 1, sealed at each end in a water- tight manner and adapted to contain rechargeable electric batteries. A lamp 9, is provided at one end and the other end has a socket fitting for connection to an electrical source for charging the batteries. A handle 2, is fixed to the body and has magnet means 33, associated with it for operating switch means inside the body for operating the lamp. An audible alarm system may be incorporated in the lamp. <IMAGE>

Description

SPECIFICATION Improvements in or relating to underwater lamps This invention relates to an underwater lamp for use by divers, skindivers and others.

There is a great need for a robust, simple and powerful underwater lamp for use by divers and others, particularly in the waters around the United Kingdom. With underwater lamps at present available , it is a disadvantage that the batteries have to be replaced at short intervals, which means opening and closing a casing of the lamp leading to weakness and possible leakage of water into the lamp. It is also a disadvantage that the on/off switch is a source of weakness through which leakage may also occur.

It is an object of the invention to provide an underwater lamp for use by divers and others which is simple to use and in which the risk of leakage is reduced.

According to the present invention there is provided an underwater lamp. comprising a hollow substantially cylindrical body sealed at each end in a water-tight manner and adapted to contain a plurality of rechargeable electric batteries, a lamp at one end a socket fitting at the other end for connection to an electrical source for charging said batteries, a handle to the body, switch means inside the body and magnet means associated with the handle for operating the switch means.

As the switch means is operated magnetically, there is no penetration of the body in the region of the switch means such as could lead to leakage and subsequent failure. If desired an audible alarm system may be incorporated in the lamp especially for recall purposes or for use in murky waters.

In order to enable the invention to be more readily understood, reference will now be made to the accompanying drawings, which illustrate diagrammatically and by way of example an embodiment thereof, and in which: Figure 1 is a perspective view of an underwater lamp, Figure 2 is a longitudinal section through the lamp shown in Fig. 1, and Figure 3 is a wiring diagram of the lamp.

Referring now to Figs. 1 and 2 of the drawings, there is shown an underwater lamp. having a body 1 in the form of a hollow tube of plastics material, such as rigid polyvinyl chloride tube. A handle 2 also of plastics material is fixed to the body 1 and comprises a hollow cylindrical part 3 which is held paraliel to and spaced from the body 1 by legs 4. The legs 4 are secured to the body, in a manner not shown, by screws passing through the body 1 from the inside of the body into the legs 4, there being O-ring seals between the mating surfaces of the body and the legs. Alternatively, the legs 4 may be adhered to the outside of the body 1 in such a way that there is no penetration of the body by any securing means at the places where the legs are attached.

As shown in Fig. 2, the body 1 is in the form of a hollow cylinder of plastics material, machined from right cylindrical stock so as to have a forward internal rib 5, a rear internal rib 6, and internal screw threading 7 and 8 at the front and rear ends respectively. A bulb unit 9 comprising a bulb 10, reflector 11 and cover glass 12 is inserted into the front end of the body until it abuts against the internal rib 5. It is then held in place by a cylindrical sealing ring 14 in the outer surface of which a rubber O-ring 15 is mounted, the sealing ring with its O-ring 15 also being inserted into the front end of the body. A further rubber O-ring seal 16 is then inserted to lie adjacent the edge of the ring14 and a disc 17 of transparent plastics material such as that known under the Registered Trade Mark "Perspex" is placed against the O-ring seal 16.Finally, an externally threaded ring 18 is screwed onto the threading 7 so as to press the disc 1 7 against the O-ring 16 and to provide a watertight seal.

The rear end of the body 1 is also sealed in a water-tight manner with a cylindrical ring 20 bearing against the rear internal rib 6 and a further disc 21 of plastics material pressed against a rubber O-ring 22 by an externally threaded ring 23 engaging in the threading 8.

The disc 21 is, however, formed with a central aperture to receive a threaded socket holder 24 having a flange 25 adhered to the disc 21. An internally threaded end cap 26 is provided for covering the end of the socket holder 24, the end cap 24 carrying at its end an O-ring seal 27 for engaging against the disc 21 whereby a water-tight seal may be obtained, and the end cap being externally knurled as at 28.

The body houses twelve 1. 1 5v nickel/cadium batteries arranged in two series each of six batteries and connected in an electrical circuit to be described with reference to Fig. 3.

Mounted in the body 1 in recesses in the forward internal rib 5 are two micro-reed switches 30 and 31 each of which is arranged to be operable by a magnet. A plunger 32 in the form of a hollow tube is mounted in the forward end of the handle 2 and carries at its end a magnet 33 for operating the switches 30 and 31. The plunger 32 is spring-loaded by a spring 34 into an off-position and may be moved into each of two separate on-positions by an arm 35 which projects from the end of the handle and can be placed in either of two branches of a slot 36 in the end of the handle. When the arm 35 is placed in the first branch of the slot 36, the light is switched on via the micro-reed switch 30 due to the operation of the respective switch by the magnet 33.The upper end of the plunger tube 32 is closed by a cap 37 of plastics material and may be engaged by the thumb of the operator to depress the plunger and operate the lamp.

The present lamp is designed to be rechargeable and to this end the socket fitting 24 is designed to be connected via a length of cable (not shown) to the cigar/cigarette lighter socket of a motor car. The twelve batteries are arranged in two series or banks 40 and 41 so that both banks can be charged at a time via a charge resistor 42.

Referring now to Fig. 3, there is shown the circuit diagram for the lamp. The circuit has connections 43 and 44 for connection to the lighter socket of a motor car and thus to the car battery, a 1 2v D.C. source used for charging. The circuit also includes a relay 45 with a 6v relay coil 46 operable by the micro-reed switch 31 to place the two banks of batteries in series with the bulb 10 which is a 12v 55w bulb. When the switch 31 is in the off position, as shown, the two banks of batteries are connected to the socket holder for charging. Two diodes 47 and 48 are arranged in the circuit and so arranged as to prevent the discharge by one bank of batteries into the other while the light is not used and the batteries are not being charged.The second micro-reed switch 31 is arranged to place in circuit an alarm signal device 49 in the form of a buzzer or other device for generating an audible signal which is more readily perceptible to a diver in murky waters than a light may be and which can also be used as an alarm or recall signal.

It will be appreciated that the present lamp is simple and robust. Each end of the hollow body 1 is sealed in a water-tight manner and since the seal at the body is not disturbed to replace batteries the risk of failure through leakage of water into the body is reduced.

The only seal which needs to be broken periodically is that provided by the O-ring seal 27 when the end cap 26 is removed to permit the batteries to be charged. The use of the magnet 33 to operate the switches 30 and 31 further ensures that there is no possibility for failure through leakage to occur in the region of the switches.

Claims

1. An underwater lamp comprising a hollow substantially cylindrical body sealed at each end in a water-tight manner and adapted to contain a plurality of rechargeable electric batteries, a lamp at one end, a socket fitting at the other end for connection to an electrical source for charging said batteries, a handle to the body, switch means inside the body and magnet means associated with the handle for operating the switch means.

2. An underwater lamp as claimed in Claim 1, wherein an audible alarm system is incorporated in the lamp.

3. An underwater lamp as claimed in Claim 2, wherein the switch means comprises two micro-reed switches, and the magnet means is movable to two positions in the handle in order to operate each of the switches in turn, one switch serving to operate the lamp and the other serving to operate the audible alarm system.

4. An underwater lamp as claimed in any one of Claims 1 to 3, wherein the magnet means is incorporated in a plunger mounted for movement in the handle.

5. An underwater lamp substantially as hereinbefore described with reference to the accompanying drawings.